Does Your Sewer Line Need Replacing or Descaling?
3 pros!
Learn how removing scale deposits from your cast-iron pipe can save cash and avoid a clogged drain.
Has a plumber told you that your home’s sewer line needs to be replaced? Maybe shown you photos of the pipe’s interior, heavily coated with scale?
If your house was built before the mid-1970s and still has its original sewer system, it’s likely that a portion of that system is cast iron. We receive phone calls every day from homeowners inquiring about replacing a cast-iron sewer line.
However, unless your home is at least 50-60 years old, it’s likely your cast-iron sewer pipe is in perfectly functional condition.
“But the plumber said my drain needs to be replaced”
After years of normal use, corrosion deposits adhere to the inner walls of the cast-iron pipe through a process called tuberculation. After 25-30 years, corrosion deposits usually have taken over 25 percent of the cast-iron pipe.
With every flush down the toilet, debris gets slowed or trapped by corrosion deposits. These deposits reduce the flow rate of the cast iron and eventually can cause a clogged drain.
When you call a plumber to inspect the cause of a sewer backup, the plumber will most likely run a drain camera through the sewer to inspect the condition of the pipe’s interior. Often, the plumber will see the corrosion and recommend a drain or sewer replacement.
But, what the plumber may have failed to understand is that tuberculation can be removed, which will cost you less money.
“So I don’t need to replace my cast-iron sewer pipe?”
It’s possible to remove the corrosion deposits within cast-iron drainpipe. Specialized descaling equipment can scrape the corrosion off the inner walls of the pipe, so it can be flushed down the sewer.
“Why didn’t the plumber tell me that?”
The majority of plumbing contractors don’t carry specialized descaling equipment. Most plumbers won’t tell you they can’t descale your cast-iron pipe. Typically, the plumbing contractor will try to formulate a solution for you, based on their abilities and tools.
“How long should cast-iron sewer pipes last?”
In residential use, cast-iron pipes should last 50-75 years. There are factors that can speed up deterioration, but the typical cast-iron sewer should reach this age before it needs replacing.
“What causes cast-iron sewer pipe to corrode more rapidly?”
Grease.
As a sewer contractor who has been working with drainpipes for the last 15 years, I can tell you that washing grease down the drain is the No. 1 cause of cast-iron degradation. Acidic soil, detergents and drain chemicals also can contribute to decreasing the longevity of cast-iron pipe.
Special power-operated grinding equipment can remove scale from the inside of cast-iron pipes. (Photo courtesy of Legendary Home Services)
“What should I do about the sewer line now?”
If you are facing a possible replacement, look for a contractor who can descale the cast-iron pipes with power-operated grinding equipment that’s specially designed for the task. You’ll be saving money over the cost of sewer line replacement.
“Is there a difference between descaling and hydrojetting?”
Hydrojetting may not be sufficient for proper descaling. Many plumbers think a simple sewer line cleaning with high-pressure water will remove scale. With the right nozzles and cleaning tool (head) on the end of the hose, this equipment is capable of removing scale. But simply using high-pressure water will, more often than not, fail to remove the bulk of the deposits.
As of February 9, 2017, this service provider was highly rated on Angie's List. Ratings are subject to change based on consumer feedback, so check Angie's List for the most up-to-date reviews. The views expressed by this author do not necessarily reflect those of Angie's List.
